Question

Two point charges, Q1 and Q2, are located at (0,5,-1) and
(0,-2,6) respectively. Find the relation between Q1 and Q2 such
that a test charge at point p(0,2,3) will have no
y-component.

I started out by finding OQ1 =
ay5-az and
OQ2 =
-ay2+az6,
making Q1Q2 =
ay7-az7,
and I know OP =
ay2+az3,
but I am stumped at where to go from here. I think I have to use
the equation F12 =
q2E12 = , but I just don't see how.